Work will continue on the way in which inert solutes, e.g., hydrophobic salts and nonionic solutes can modify the surface of a micelle or liposome, and the use of kinetic probes will be the main method. The work on chemical hydrolyses of phosphate esters will focus on attempts to obtain phosphorylation of -NH2 or -SH groups, usually by changing the microscopic environment for reaction. We plan to exploit periodate oxidation as a possible assay method for thyroxine and related compounds, and as a simple assay method for RNA in the presence of DNA. This latter aspect of our work applies well understood chemical reactions to assay of complex biological molecules, but the main thrust of the work will continue to be a study of the way in which reactions occurring at an interface between water and a molecular aggregate can be controlled, and we believe that some of the hydrophobic interactions which we are now observing may be of great importance in controlling conformation and reactivity at a biological surface, and may be more important than such generally recognized interactions as hydrogen bonding.